1. Field of the Invention
The present invention is generally related to a method for controlling the operation of a marine vessel and, more particularly, to a method that monitors both the current position of a marine vessel and a planned waypoint, along with several other variables, to determine whether the vessel has sufficient fuel to reach the planned waypoint. The method for controlling the marine vessel can be automatic or can comprise suggesting certain control changes (e.g. engine speed) to an operator of the vessel.
2. Description of the Prior Art
Many systems are available for determining the location of a marine vessel or other type of vehicle. Marine vessels are typically provided with various sensors that also monitor the current status of operational variables relating to the marine vessel. For example, modern watercraft are usually provided with sensors that measure the engine speed (RPM), vessel speed (MPH), available fuel in a fuel tank (gallons), and various other parameters. Using a global positioning system (GPS), the current location of the marine vessel can be accurately determined. By comparing sequential GPS locations as a function of time, the speed of the marine vessel can be accurately calculated. In addition, the distance between a desired waypoint and the current position of the marine vessel can be calculated.
U.S. Pat. No. 5,355,140, which issued to Slavin et al on Oct. 11, 1994, describes an emergency reporting system for marine and airborne vessels.
The method and apparatus are disclosed for reporting an emergency event experienced by a marine vessel, an airborne vessel or by an occupant of the vessel. The present vessel position, accurate to within a few tens of meters, and the vessel velocity and local air quality is determined at an ordered sequence of times, using a position-determining Global Positioning System, such as the Navstar system or the GLONASS system. If an emergency occurs on the vessel, the approximate present position and time of occurrence of this event is broadcast on one or more of the mobile communication or emergency radio wave bands. Optionally, the type of emergency event that has occurred drawn from a predetermined list of such types, is also broadcast by a vessel in distress, for receipt by an emergency response facility or by another vessel that can respond to a call for assistance. Optionally, the vessel velocity heading and/or vessel position quality of fixed information is also broadcast by a vessel in distress.
U.S. Pat. No. 5,491,636, which issued to Robertson on Feb. 13, 1996, describes an anchorless boat positioning process employing global positioning systems. An anchorless boat positioning system dynamically and automatically maintains a boat at a selected anchoring location within water without the use of a conventional anchor by using a steerable thruster whose thrust and steering direction are determined on the basis of position information signals received from global positioning system (GPS) satellites and heading indication signals from a magnetic compass. The anchorless positioning system continuously monitors the position and heading of the boat and compares it with the stored coordinates of the selected anchoring location to generate control signals for a steerable motor.
U.S. Pat. No. 5,731,788, which issued to Reeds on Mar. 24, 1998, describes a global positioning and communications system and a method for race and start line management. A system and method for positioning control and management of racing sailboat positions and velocities includes the strategic placement of global positioning receivers and transmitters at a buoy and committee boat marking the sail race start line, as well as radio and global positioning receivers on the sailboat. Global positioning system (GPS) and radio transmitter units are mounted on a race start buoy and committee boat and another GPS and radio transceiver unit receives GPS signals from positioning satellites and radio signals from the race start buoy and committee boat. The information received by the racing sailboat is processed to determine relative and absolute positions and velocities, and estimated time of arrival (ETA) at the intercept between current sailboat course and race start line for display in user-friendly race management.
U.S. Pat. No. 5,386,368, which issued to Knight on Jan. 31, 1995, so describes an apparatus for maintaining a boat in a fixed position. An apparatus for maintaining a floating boat or water vessel in a desired position is provided. The apparatus includes an electric trolling motor disposed to produce a thrust to pull the boat, a steering motor disposed to affect the orientation of the electric trolling motor, a position deviation detection unit, and a control circuit. The position deviation detection unit detects a deviation in the position of the boat from the desired position and transmits signals indicative of a deviation distance (the distance from the boat to the desired position) and a return heading (the direction of the desired position from the boat) to a control circuit. The control circuit causes the steering motor to steer the electric trolling motor in the return heading, and the electric trolling motor to propel the boat in the return heading, to return the boat to the desired position.
U.S. Pat. No. 5,884,213, which issued to Carlson on Mar. 16, 1999, describes a system for controlling navigation of a fishing boat. A system for controlling the navigation of a fishing boat between waypoints representing successive positions around a navigation route is described. The system includes an input device for setting the waypoint positions, a position detector to detect the actual position of the fishing boat, a trolling motor to produce a thrust to propel the fishing boat, a steering motor to control the direction of the thrust, and a heading detector to detect the actual heading of the fishing boat. The system also includes a control circuit which determines a desired heading using a desired waypoint and the actual position of the fishing boat, and generates a steering control signal applied to the steering motor to steer the fishing boat from the actual position to the desired waypoint. The system operates in various modes which allow repeated navigation of the fishing boat around a navigation route. The system provides for automatic waypoint storage as the fishing boat is maneuvered around navigation route.
It would be significantly beneficial for the operation of a marine vessel if a system could be provided that determine whether or not the marine vessel has sufficient fuel onboard to allow it to travel along a planned course to a desired waypoint. In one typical application, such a system would be used to assure that the marine vessel has sufficient fuel to return to its home port after the marine vessel has journeyed away from the home port on a body of water.
The patents described above are hereby expressly incorporated by reference in the description of the present invention.